Melasma

Question 1

Incidence

Answer 1

Incidence: 90% F
9% Hispanics
40% south east Asians

Question 2

Exacerbating factors

Answer 2

Exacerbating factors: pregnancy, OCP, UV light, visible light (darker pigmentation, more sustained), autoimmune thyroid disease, phenytoin, phototoxic drugs

Question 3

Aetiology

Answer 3

UV induced upregulation of melanocyte stimulating cytokines

Increased vascularity and increased VEGF in epidermis. Which is why Pulsed dye and transexamic acid may help

Question 4

Locations

Answer 4

Brown macules or pattern in centrofacial (most common), malar or mandibular region. Most often overlapping. Rarely affects below the mandible. Face> forearms

Question 5

Problem with wood’s lamp

Answer 5

Wood’s lamp may help, but often limiting – in theory epidermal more obvious. Usually mixed: epidermal/dermal

Question 6

Scoring system

Answer 6

MASI: melasma area & severity index. (0-48)
A)area of involvement
D) darkness
H) homogeneity in the forehead, right malar, left malar, chin
Then consider % surface area

Question 7

DDx

Answer 7

DDx:
Naevus of Ota, Hori’s naevus, Medication induced hyperpigmentation 
Erythema dyschromia perstans
LPP
Lichenoid drug
Riehl’s melanosis
Post inflammatory pigmentation
Maturational dyschromia
Periorbital hyperpigmentation
Acanthosis nigricans
Lentigines
Exogenous ochronosis.

Question 8

DDx if lateral forehead or nasolabial folds

Answer 8

If lateral forehead- think drug induced or LPP

Nasolabial folds spared (drug – often involved)

Question 9

Histology

Answer 9

Histo: melanocytes contain and increased no of melanosomes. Increased melanin deposition is in all layers of the epidermis.

Question 10

Treatment - general measures

Answer 10

Photoprotection, particularly with physical blockers and iron oxide 3.2% containing sunscreens or make up. Consider computer screen protectors and tinted car windows.
Consider checking baseline Vit D levels
Cosmetic camouflage

Question 11

DDx of facial hyperpigmentation

Answer 11

Squamous: Riehl’s melanosis (contact allergy) or Berloque dermatitis, PIH, erythromelanosis follicularis faceiei et colli
Infiltrates: mastocytosis
Naevus of ota like macules
Drugs: minocycline, photosensitive drug, amiodarone, argyria, exogenous ochronosis , OCP
Immune: LP, actinic type, LPP, erythema dyschromicum perstans
Physical: facial erythema ab igne, PMLE, poikiloderma of civatte
Metabolic: Liver disease, haemachromatosis.
Endocrine: Melasma, addisons
Nutritional: Kwashiorkor, pellagra, sprue, Vit B12 deficiency

Question 12

Kligman-Willis combination?

Answer 12

Kligman-Willis combination and variants : dex 0.1%, hydroquinone 5%, tretinoin 0.1%. Daily for 12/52, then twice weekly maintenance.

Question 13

Peels that could be used

Answer 13

Glycolic acid – alpha hydroxyl acid 
20-70%
Lactic acid 
Sal acid 
TCA 10-20%
Tretinoin
Other

Question 14

Glycolic acid peels

Answer 14

Reduction in melasma, but similar from hydroquinone or dual topicals. Optimal concentration is 53%. May marginally help in combination with 5% Hydroquinone 0.05% tretinoin 1% HC

Question 15

Laser?

Answer 15

Last resort considering risk of PIH
IPL 560nm cut off filters: avoid in darker skin types
Q switched lasers eg Nd:YAG
Erb: YAG: not effective
Non ablative 1550nm fractional laser (erb: glass) – as effective as 15% TCA peel
Fractional 1927 laser – studies not convincing

Question 16

Systemics

Answer 16

Oral transexamic acid : thought it decreases tyrosinase activity and possibly increases VEGF
SE: menstrual irregularity, headaches, naeusa and back pain
No evidence for increase in thrombotic events in doses up to 3.9-4g/day for 4-5/7 per cycle
500mg daily if failed or are intolerant of hydroquinone. Trial 6-12 months. Attempt to transition to topical maintenance with sunscreen + topical retinoid.

Question 17

Possible regimes

Answer 17

1) 0.1% tretinoin, 1% HC, 4-6% HQ +0.5% Ascorbic acid in aqueous cream nocte
2) 20% topical azelaic acid for epidermal
3) 4% HQ twice daily
RV at 8 weeks
4) 30% GA peel up to 3min then increasing in duration and concentration every 4-6 weeks as tolerated
5)2.5% kojic acid + 2.5% hydroquinone + 1% HC